Combined use of SCADA and PMU measurements for power system state estimator performance enhancement

State estimator is vital for on-line power system monitoring, analysis and control. With the increasing use of synchronized phasor measurement units (PMU) in power grids, how to utilize phasor measurements to improve the precision of state estimator becomes imperative. In this paper, a state estimator including voltage phasors, injected current phasors and traditional measurements is proposed. 14 IEEE bus system and 30 IEEE bus system are used as test systems and the simulation results demonstrate that the presented state estimation algorithm combining traditional SCADA measurements with PMU (Phasor Measurement Unit) measurements for power system state estimation improves the precision greatly.